Corrosion resistant alloy



1 geous which contain UNITED: STATES PATENT OFFICE CORROSION RESISTANT ALLOY Carl Carius, Essen, Germany, assignor to Fried. Krupp Aktiengesellschalt, Essen-on-the-Ruln',

Germany No Drawing. Application June 28, 1935, Serial No. 28,943. In Germany September 13, 1934 3 Claims. (Cl. 75-125) The invention relates to corrosion-resistant alloys and has more particularly reference to corrosion-resistant chromium-nickel-iron alloys which according to the invention further contain antimony. Alloys of this composition are distinguished by a very high resistance to corrosion and are in particular far superior to the usual chromium-nickel-molybdenum-iron alloys, for example'to the known austenitic chromium-nickelmolybdenum steels, as to resistance to caustic soda lye or potash lye and in particular to hydrochloric acid. The invention further includes their'nprovement of alloys 01' this class by adding copper to them.

The alloys according to the invention may be composed about as follows:

I Percent Carbon to 1 Chromium '10 to.25 NickeL 20 to 40 Molybdenum 1 to Antimony 2 to 'l Copper 0 to 10 and the remainder iron, without or with the normal impurities.

Alloys have been proved particularly advanta- Percent Carbon less than 0.2 Chromium 13 to Nioke1- 27 to 33 Molybdenum 2 to 5 Antimony 3 to 5 and the remainder iron, without or with the normal impurities, and, under circumstances, further Percent Copper v 2 to 6 An alloy, for example, containing Percent Carbon 0.15 --Chromium p 18 Nickel I so Molybdenum 5 Antimony 5 Copper i 5 and the remainder iron, without 01' with the normal impurities, was not attacked to an extent I worth mentioning by 20%- hot hydrochloric acid.

Analyses Symbol of the auoy C Si Mn (r h 1 Mo Sb Cu 10 '7 9 7 '7- I 0. 34 07%: 0. 0 11. a 30. 3 5.5 v5. Z. a II 0. O1 0. 37 0. 39 18. 9 29. 9 5. 45 2. U3 5. 0 III 0. 04 0. 40 0. 1S. 4 30. 2 5. 3 5. 1 IV 0. 02 0. 27 0. 44 18. 3 29. 5 5.

' Loss of weight of the Conoen- Temper castings alter 200 hour Corrosive agent g atures in test m 3' mm percent I II- III IV 0.3 0.39 1.8 at RC] 10 U. 5 0. 57 3. 6 2. 5 80 0. 7 0. 78 8. 0 15. O 40 0. 3 0. 41 1. 9 I. 0 [TC] 15 60 0. 4... 0. 4 3 -5. 0 4.0 80 0.10 0.78 11.0 10.0 40, 0.45 0.30 2.1 1.9 H01 2o 6!) 0. 5 0. 29 (i. 2 5. 0 so 3.9 0.95 20.0 17.0 40 0. 0. 50 3. 6 2. 0 BC] 25 60 1. 0 0. 10. 0 6. 0 so i. 9 3. 0 a0. 0 20. 0

In order to impart to the alloys particularly a good properties, they may be subjected to a heat treatment as usual with corrosion-resistant steels.

What I claim and desire to secure by Letters Patent is:-

1. An alloy of the class described and containing 0.024% carbon, 10-25% chromium,

20-40% nickel, 1-10 ;o molybdenum, 24% antimony, 05-10% copper, and the remainder iron.

2. An alloy 0! the class described and containing 0.02-0.2% carbon, 13-20% chromium, 27-33% nickel, 2-5%molybdenum, 34% antimony, 2-6% 5 copper, and the remainder iro 3. An alloyv oi the class described and containin; 0.15% carbon, 18% chromium,'30% nickel,

5% molybdenum, 5% antimony, 5% copper, and the remainder iron.

cam. caarus. 

